fix: keep scheduled audio when a clip ends during an export

packages/runtime/src/media/audio.ts

@@ -228,17 +228,26 @@ export class AudioDecoder {
 	}
 
 	public reset() {
+		this.release();
+
+		for (const node of this.audioNodes) {
+			node.stop();
+		}
+		this.audioNodes.clear();
+	}
+
+	/**
+	 * Drops the decoding state but lets buffers that are already scheduled play out.
+	 * `renderData` truncates every scheduled buffer at the clip's `trimEnd`, so the
+	 * nodes stop on their own at the clip's out point and `onended` removes them.
+	 */
+	public release() {
 		if (!this.iterator) return;
 
 		this.iterator?.return();
 		this.iterator = null;
 		this.firstBuffer = null;
 		this.lastBuffer = null;
-
-		for (const node of this.audioNodes) {
-			node.stop();
-		}
-		this.audioNodes.clear();
 	}
 }
 

packages/runtime/src/systems/playback.ts

@@ -196,6 +196,13 @@ function forwardAudioDecoder(world: World, scene: Entity, entity: Entity, audioS
 			relativeDelay: (origin / fps) + audioDelay,
 		});
 		framePromises(world)?.push(playPromise);
+	} else if (world.get(Mode)?.value !== 'realtime') {
+		// Offline rendering: the OfflineAudioContext runs behind the frame loop (the
+		// encoder lets it lag by up to a second of samples). Stopping the nodes here would
+		// cut the part of the clip the audio thread has not rendered yet, so every clip
+		// that ends before the scene does would lose its tail in the export. The scheduled
+		// buffers already end at the clip's out point, so let them finish.
+		decoder.release();
 	} else {
 		decoder.reset();
 	}